Soil Properties
Cyclic1D has 15 predefined materials that the user can choose from. Basic model parameter values for these 15 materials are listed below.
Cohesionless Soil | Shear wave velocity at 10m depth1,2 (m/s) | Friction angle3 (degrees) | Possion's ratio | Permeability coeff.4 (m/s) | Mass density5 (kg/m3) |
Loose, silt permeability | 185 | 29 | 0.4 | 1.0x10-7 | 1.7x103 |
Loose, sand permeability | 185 | 29 | 0.4 | 6.6x10-5 | 1.7x103 |
Loose, gravel permeability | 185 | 29 | 0.4 | 1.0x10-2 | 1.7x103 |
Medium, silt permeability | 205 | 31.5 | 0.4 | 1.0x10-7 | 1.9x103 |
Medium, sand permeability | 205 | 31.5 | 0.4 | 6.6x10-5 | 1.9x103 |
Medium, gravel permeability | 205 | 31.5 | 0.4 | 1.0x10-2 | 1.9x103 |
Medium-dense, silt permeability | 225 | 35 | 0.4 | 1.0x10-7 | 2.0x103 |
Medium-dense, sand permeability | 225 | 35 | 0.4 | 6.6x10-5 | 2.0x103 |
Medium-dense, gravel permeability | 225 | 35 | 0.4 | 1.0x10-2 | 2.0x103 |
Dense, silt permeability | 255 | 40 | 0.4 | 1.0x10-7 | 2.1x103 |
Dense, sand permeability | 255 | 40 | 0.4 | 6.6x10-5 | 2.1x103 |
Dense, gravel permeability | 255 | 40 | 0.4 | 1.0x10-2 | 2.1x103 |
Cohesive Soil | Shear wave velocity (m/s) | Undrained shear strength6 (kPa) | Possion's ratio | Permeability coeff.4 (m/s) | Mass density5 (kg/m3) |
Soft | 100 | 18.0 | 0.4 | 1.0x10-9 | 1.3x103 |
Medium | 200 | 37.0 | 0.4 | 1.0x10-9 | 1.5x103 |
Stiff | 300 | 75.0 | 0.4 | 1.0x10-9 | 1.8x103 |
U-Clay/Rock | User-defined | Used-defined | 0.4 | 1.0x10-9 | User-defined |
Base Boundary Condition
Bed rock type | Shear wave velocity7 (m/s) | Mass density (kg/m3) |
Rigid base | Infinite | N/A |
Soft rock | 700 | 2.5x103 |
Medium rock | 1100 | 2.5x103 |
Hard rock | 1600 | 2.5x103 |
Total transmitting | Same as bottom layer | Same as bottom layer |
U-Rock | User-defined | User-defined |
1. Shear wave velocity of cohesionless soils varies
approximately in proportion to (pm)1/4
where pm
is effective mean confinement.
2. Shear wave velocities for cohesionless soils are based on the empirical formula of Seed, H.B. and Idriss, I.M. (1970). "Soil moduli and damping factors for dynamic response analyses," Report EERC 70-10, Earthquake Engineering Research Center, University of California, Berkeley.
3. Friction angles for cohesionless soils are based on Table 7.4 (p.425) of Das, B.M. (1983). Advanced Soil Mechanics, Taylor and Francis Publisher.
4. Permeability values are based on Fig. 7.6 (p.210) of Holtz, R.D. and Kovacs, W.D. (1981). An Introduction to Geotechnical Engineering, Prentice Hall, Englewood Cliffs, New Jersey.
5. Mass density is based on Table 1.4 (p.10) of Das, B.M. (1995). Principles of Foundation Engineering, Third Ed., PWS Publishing Co., Boston, MA.
6. Undrained shear strength for cohesive soils are based on Table 7.5 (p.442) of Das, B.M. (1983). Advanced Soil Mechanics, Taylor and Francis Publisher.
7. Shear wave velocities for rocks are based on International Code Council (1998). 2000 International Building Code (Final Draft).